`CH_3-underset(CH_3)underset(|)(CH)-underset(CH_3)underset(|)overset(CH_3)overset(|)(C )-CH_2Br underset(HOH)overset(NaOH)(rarr)`
Consider the following statement for the given reaction
1. The reaction is `S_N1`
2. The reaction intermediate is carbocation
3. The major product will be 2,3-dimethyl-3-pentanol
4. The major product has one stereogenic centre

Options

A. 1,2 and 3 are correct
B. 2,3 and 4 are correct
C. 1,2,3 and 4 are correct
D. 1,3 and 4 are correct

Answer

To solve the given problem, we will analyze the hydrolysis of the haloalkane step by step and evaluate the provided statements.

### Step 1: Identify the Reaction
The reaction involves the hydrolysis of a haloalkane (specifically, a bromoalkane). The structure given is CH3-CH(CH3)-C(CH3)-CH2Br. The reaction is performed in the presence of water (H2O) and sodium hydroxide (NaOH).

**Hint:** Hydrolysis of haloalkanes typically involves the substitution of the halogen (Br in this case) with a hydroxyl group (OH).

### Step 2: Determine the Mechanism
The mechanism of the reaction can be either SN1 or SN2. In this case, we have a tertiary carbon (due to the presence of three alkyl groups attached to the carbon bearing the Br). Tertiary haloalkanes generally favor the SN1 mechanism due to steric hindrance.

**Hint:** Remember that primary haloalkanes typically follow the SN2 mechanism, while tertiary haloalkanes follow the SN1 mechanism.

### Step 3: Formation of Carbocation
In the SN1 mechanism, the first step is the formation of a carbocation after the leaving group (Br) departs. The leaving of Br generates a carbocation intermediate. Since the starting haloalkane is tertiary, the carbocation formed will be stable.

**Hint:** The stability of carbocations increases with the number of alkyl groups attached to the positively charged carbon.

### Step 4: Carbocation Rearrangement
After the formation of the carbocation, if it is a 1-degree carbocation, it may undergo rearrangement to form a more stable carbocation. In this case, a methyl shift occurs, converting the 1-degree carbocation into a more stable 3-degree carbocation.

**Hint:** Look for possible rearrangements that lead to more stable carbocations.

### Step 5: Nucleophilic Attack
The next step involves the nucleophile (water in this case) attacking the carbocation. The oxygen in water has lone pairs and can act as a nucleophile, forming an alcohol.

**Hint:** The nucleophile will attack the positively charged carbon to form the alcohol.

### Step 6: Final Product Formation
After the nucleophilic attack, the final product is formed by deprotonation of the hydroxyl group. The resulting compound is 2,3-dimethyl-3-pentanol.

**Hint:** Make sure to account for all groups attached to the final product to confirm its structure.

### Step 7: Evaluate the Statements
1. **The reaction is SN1** - Correct, as discussed.
2. **The reaction intermediate is carbocation** - Correct, as the carbocation is formed during the reaction.
3. **The major product will be 2,3-dimethyl-3-pentanol** - Correct, as we derived this product.
4. **The major product has one stereogenic center** - Correct, as the carbon with the hydroxyl group is a chiral center.

### Conclusion
All four statements are correct.

**Final Answer:** All statements (1, 2, 3, and 4) are correct.